JP2000093997A - Nitrate nitrogen denitrifying substrate - Google Patents
Nitrate nitrogen denitrifying substrateInfo
- Publication number
- JP2000093997A JP2000093997A JP10271920A JP27192098A JP2000093997A JP 2000093997 A JP2000093997 A JP 2000093997A JP 10271920 A JP10271920 A JP 10271920A JP 27192098 A JP27192098 A JP 27192098A JP 2000093997 A JP2000093997 A JP 2000093997A
- Authority
- JP
- Japan
- Prior art keywords
- sulfur
- weight
- parts
- calcium carbonate
- substance
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- Purification Treatments By Anaerobic Or Anaerobic And Aerobic Bacteria Or Animals (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、硝酸性窒素の除
去，即ち、脱窒素による水質浄化に用いられる硝酸性窒
素脱窒基質に関するものである。The present invention relates to a nitrate nitrogen denitrification substrate used for removing nitrate nitrogen, that is, for purifying water by denitrification.
【０００２】[0002]
【従来の技術】水質を浄化するための硝酸性窒素除去技
術のうち、例えば、メタノールや汚泥中の有機炭素源を
水素供与体として従属栄養性脱窒を行わせる方法は従来
から知られている。この方法は目的微生物以外の分解系
の影響を受け、基質当たりの脱窒効率は低いが、比較的
簡単に硝酸性窒素を脱窒させることができるので、脱窒
処理に用いたメタノールや汚泥を外界に排出しないよう
厳しく管理された処理設備において実施される。即ち、
単一の脱窒槽に非処理水を通水するだけでは脱窒操作を
完了させることができず、多くの処理過程や処理槽・設
備が必要となる。2. Description of the Related Art Among nitrate nitrogen removal techniques for purifying water quality, for example, a method of performing heterotrophic denitrification using methanol or an organic carbon source in sludge as a hydrogen donor has been known. . This method is affected by decomposition systems other than the target microorganism, and has a low denitrification efficiency per substrate.However, since nitrate nitrogen can be denitrified relatively easily, the methanol and sludge used in the denitrification treatment can be removed. It is carried out in processing equipment that is strictly controlled so as not to be released to the outside world. That is,
Simply passing non-treatment water through a single denitrification tank cannot complete the denitrification operation, and requires many treatment steps and treatment tanks and equipment.
【０００３】従って、窒素成分の大部分が無機態の硝酸
性窒素であり、近年、その濃度について問題提起されつ
つある耕地の暗渠排水等には適用させることが困難であ
った。また、処理流量および含有される硝酸性窒素に合
わせて脱窒基質を的確に注入しなければ新たな水質汚染
を発生させてしまうことから、このような従属栄養性脱
窒の実施には、下水処理場のような設備や常時行き届い
た管理が要求される。[0003] Therefore, most of the nitrogen component is inorganic nitrate nitrogen, and it has been difficult to apply it to culvert drainage of cultivated land, etc., whose concentration has recently been raised as a matter of concern. In addition, if the denitrification substrate is not properly injected in accordance with the treatment flow rate and the contained nitrate nitrogen, new water pollution will be generated. Equipment such as a treatment plant and careful management are always required.
【０００４】これに対し、硫黄や硫黄化合物を用いた独
立栄養性脱窒では硫黄酸化細菌による脱窒に限定される
ため、基質当たりの脱窒効率が高く、しかも反応産物で
ある硫酸イオンは水質環境の制限因子ではないので、処
理水中に０．１％以下の含有率であれば、カルシウム化
合物によるｐH調整を行うことにより処理水をそのまま
放流できる利点がある。On the other hand, autotrophic denitrification using sulfur or a sulfur compound is limited to denitrification by sulfur-oxidizing bacteria, so that the denitrification efficiency per substrate is high and the sulfate ion as a reaction product is water quality. Since it is not a limiting factor of the environment, if the content of the treated water is 0.1% or less, there is an advantage that the treated water can be discharged as it is by adjusting the pH with a calcium compound.
【０００５】この硫黄や硫黄化合物を用いた独立栄養性
脱窒の方法として、例えば特公昭62-56798号公報、特公
昭63-45274号公報、特公昭60-3876号公報、特公平01-31
958号公報、特公平04-9119号公報、特開平04-74598号公
報、特開平04-151000号公報、特開平04-197498号公報、
特開平06-182393号公報記載の各方法が提案されてい
る。[0005] Autotrophic denitrification methods using sulfur and sulfur compounds include, for example, JP-B-62-56798, JP-B-63-45274, JP-B-60-3876, and JP-B-01-31.
958 No., JP-B-04-9119, JP-A-04-74598, JP-A-04-151000, JP-A-04-197498,
Each method described in JP-A-06-182393 has been proposed.
【０００６】このうち、特公昭62-56798号公報および特
公昭63-45274号公報記載の方法は、様々な種類の窒素化
合物や硫黄化合物を含有する排水の処理方法として発明
されたものであり、各々ｐH３以下での前処理や、種汚
泥として硫黄酸化細菌群を優占種とした活性汚泥を育成
するなどの段階を必要としており、硝酸性窒素を主な脱
窒対象とした場合には効率の良い方法とは言えない。Among them, the methods described in JP-B-62-56798 and JP-B-63-45274 have been invented as methods for treating wastewater containing various types of nitrogen compounds and sulfur compounds. Each requires steps such as pre-treatment at pH 3 or lower, and growing activated sludge as a dominant species of sulfur oxidizing bacteria as a seed sludge. Efficiency when nitrate nitrogen is the main denitrification target Not a good way.
【０００７】また、特公昭60-3876号公報記載の方法
や、特公平01-31958号公報記載の方法も硝酸性窒素を対
象とした脱窒方法に限定したものではないが、硝化工程
後の脱窒工程では何れも硫黄酸化細菌による脱窒を行っ
ている。しかし、硫黄成分を処理対象の硝酸性窒素量に
合わせて添加しなければならなかったり、脱窒により発
生した微細な窒素ガスを放出できずに別途曝気槽を必要
とする等から、効率の良い独立栄養性脱窒は行えない。Further, the method described in Japanese Patent Publication No. 60-3876 and the method described in Japanese Patent Publication No. 01-31958 are not limited to the denitrification method for nitrate nitrogen. In each of the denitrification steps, denitrification by sulfur-oxidizing bacteria is performed. However, since the sulfur component must be added in accordance with the amount of nitrate nitrogen to be treated, or because a fine nitrogen gas generated by denitrification cannot be released, a separate aeration tank is required, and the efficiency is high. Autotrophic denitrification cannot be performed.
【０００８】ところで、特公平04-9119号公報記載の脱
窒方法では、炭酸カルシウムから成る大理石と、硫黄粒
子を用いた排水中の窒素、燐酸の同時除去方法について
開示されているが、大理石粒と硫黄粒は同一工程内で用
いられず、しかも基本的には好気―嫌気活性汚泥処理で
あるため、硫黄のみを脱窒基質とした独立栄養性脱窒と
は異なり汚泥の管理が必要であって硝酸性窒素の直接脱
窒を行うには非効率である。[0008] In the denitrification method described in Japanese Patent Publication No. 04-9119, a method of simultaneously removing marble made of calcium carbonate and nitrogen and phosphoric acid in wastewater using sulfur particles is disclosed. And sulfur particles are not used in the same process, and are basically aerobic-anaerobic activated sludge treatment, so sludge management is necessary unlike autotrophic denitrification using only sulfur as a denitrifying substrate. Therefore, it is inefficient to directly denitrify nitrate nitrogen.
【０００９】さらに、特開平04-74598号公報記載の方法
は、基本的には嫌気―好気活性汚泥法の処理であるが、
炭酸水素ナトリウムまたは炭酸カルシウムを炭素源とし
て導入しているため、上述した各方法よりは硝酸性窒素
除去機能が安定的に発現される方法となっている。然
し、硫黄源が硫化鉄鉱であるために、脱窒効率は低く、
また、この方法もいくつもの処理槽を要する活性汚泥法
の域を出ないものであり、硝酸性窒素直接脱窒を行うに
は非効率である。Furthermore, the method described in JP-A-04-74598 is basically a treatment of an anaerobic-aerobic activated sludge method.
Since sodium hydrogen carbonate or calcium carbonate is introduced as a carbon source, the nitrate nitrogen removing function is more stably exhibited than in the above-described methods. However, since the sulfur source is iron sulfide, the denitrification efficiency is low,
Also, this method does not fall outside the range of the activated sludge method requiring a number of treatment tanks, and is inefficient for performing direct nitrification of nitrate nitrogen.
【００１０】特開平04-151000号公報記載の方法では、
炭素源として炭酸水素ナトリウムまたは炭酸カルシウム
を補給し、チオ硫酸塩を硫黄源、電子供与体とする硫黄
酸化細菌による独立栄養性脱窒について開示している
が、チオ硫酸塩を処理対象の硝酸性窒素量に見合った量
注入しなければならず、やはり硝酸性窒素の直接脱窒を
行うには非効率である。In the method described in Japanese Patent Application Laid-Open No. 04-151000,
Discloses autotrophic denitrification by sulfur-oxidizing bacteria using sodium thiosulfate as a sulfur source and an electron donor, supplemented with sodium bicarbonate or calcium carbonate as a carbon source. It is necessary to inject an amount corresponding to the amount of nitrogen, which is also inefficient for performing direct denitrification of nitrate nitrogen.
【００１１】特開平04-197498号公報記載の方法は浄水
前処理の方法として硫黄酸化細菌による独立栄養性脱窒
について開示しているが、この場合も原水に含まれる脱
窒対象量に見合った量の亜硫酸ナトリウムを添加しなけ
れば著しく効率は低下し、硝酸性窒素の直接脱窒に簡便
に適用させることはできない。The method described in Japanese Patent Application Laid-Open No. 04-197498 discloses autotrophic denitrification by sulfur oxidizing bacteria as a method for pretreatment of water purification. In this case, too, the method is suitable for the amount of denitrification contained in raw water. Without the addition of an amount of sodium sulfite, the efficiency drops significantly and cannot be easily applied to the direct denitrification of nitrate nitrogen.
【００１２】これまで述べてきた方法は何れも硝酸性窒
素の直接脱窒を目的としたものではなく、大半は活性汚
泥法の域を出ないもので脱窒という観点からすると非効
率であるが、特開平06-182393号公報記載の方法は、硝
酸性窒素を硫黄酸化細菌により効率よく脱窒できる。[0012] None of the methods described so far are intended for the direct denitrification of nitrate nitrogen, and most of them do not fall under the activated sludge process and are inefficient from the viewpoint of denitrification. In the method described in JP-A-06-182393, nitrate nitrogen can be efficiently denitrified by sulfur-oxidizing bacteria.
【００１３】ところが、該方法では硫黄酸化細菌に対
し、反応性の良い硫黄粉粒体を用いるために、硫黄粉粒
体で充填層を形成した流動床式反応槽を設備し、硝酸性
窒素等を含む原水を通水し脱窒処理を行うが、脱窒によ
り硫黄粉粒および粒体間に付着した窒素ガスを放出させ
るためには動力が必要であり、このガスを放出しないと
脱窒効率の良い硫黄粉は気泡に包まれて以後の脱窒が出
来なくなる。粒体間の気泡についても同様である。ま
た、生成される硫酸酸性を別途矯正する必要のあるこ
と、原水を常時強制通水させないと強酸性となり脱窒が
停止してしまうことなどが難点であり、例えば、広く暗
渠排水処理に用いようとしても相応の設備コストおよび
ランニングコストがかかり、普遍的な導入が困難である
という問題がある。However, in this method, in order to use sulfur granules having good reactivity against sulfur oxidizing bacteria, a fluidized bed type reaction tank having a packed bed formed of sulfur granules is provided, and nitrate nitrogen or the like is provided. Denitrification treatment is performed by passing raw water containing nitrogen, but power is required to release sulfur particles and nitrogen gas attached between particles by denitrification, and if this gas is not released, denitrification efficiency Good sulfur powder is wrapped in bubbles and cannot be denitrified thereafter. The same applies to air bubbles between particles. In addition, it is difficult to separately correct the generated sulfuric acid, and if the raw water is not forced to flow constantly, it will be strongly acidic and denitrification will be stopped. However, there is a problem in that the equipment costs and running costs are high, and universal introduction is difficult.
【００１４】それに加えて、上述した方法では硫黄と同
程度重要な炭素源の供給や、硫黄酸化細菌の活性を維持
し確実な脱窒を行うために、必要なｐＨ調整、即ちｐＨ
値を７付近に保つことについては具体的に何ら対応され
ていない。In addition, in the above-mentioned method, the necessary pH adjustment, ie, pH adjustment, is required to supply a carbon source that is as important as sulfur and to maintain the activity of sulfur-oxidizing bacteria and perform denitrification reliably.
No specific action is taken to keep the value near 7.
【００１５】水処理学界において得られた最近の知見か
らも、硫黄酸化細菌による脱窒反応を順調に行わせるた
めには、以下の内容が重要であることが示唆されてい
る。[0015] Recent findings obtained in the water treatment academy suggest that the following contents are important in order for the denitrification reaction by sulfur-oxidizing bacteria to proceed smoothly.
【００１６】それは、硫黄酸化細菌による脱窒反応を維
持継続していくために、硫黄酸化細菌の増殖を促すこと
が不可欠であり、これには栄養源である硫黄の供給のほ
か、菌体合成に必要な炭素源を確実に供給すること、微
生物活性を維持するためにｐＨ値を概ね７以上にしなけ
ればならないこと等の重要な知見である「(4-28)硫黄脱
窒法による実地下水からの硝酸性窒素除去、第４９回全
国水道研究発表会 平成10年５月、講演集ｐ２３８〜２
３９（４．浄水部門）：社団法人日本水道協会」。しか
し、ｐH値はかならずしも７以上にする必要のないこと
は以下に述べる通りである。In order to maintain and maintain the denitrification reaction by the sulfur-oxidizing bacteria, it is essential to promote the growth of the sulfur-oxidizing bacteria. Important information such as ensuring that the necessary carbon source is supplied to the soil and maintaining the pH value at about 7 or more in order to maintain microbial activity, "(4-28) From actual groundwater by sulfur denitrification method Nitrate Nitrogen Removal, 49th National Water Research Conference May 1998, p238--2
39 (4. Water purification section): Japan Water Works Association. However, as described below, the pH value does not always need to be 7 or more.
【００１７】これまで例示した通り、硝酸性窒素の安全
な脱窒に最も効果的な方法は硫黄酸化細菌による独立栄
養性脱窒であるが、従来はその効果を確実容易に発現さ
せることは困難であった。As exemplified above, the most effective method for safe denitrification of nitrate nitrogen is autotrophic denitrification by sulfur-oxidizing bacteria, but it has been difficult to express the effect easily and conventionally. Met.
【００１８】そこで、本発明者らは、これまで困難であ
った硫黄酸化細菌による独立栄養性脱窒を確実・容易に
行える微生物活性能付与組成物及びその製造方法を開発
し、出願を行った（特願平10-106974号）。Accordingly, the present inventors have developed and applied for a microbial activity-imparting composition capable of reliably and easily performing autotrophic denitrification by sulfur-oxidizing bacteria, which has been difficult so far, and a method for producing the same. (Japanese Patent Application No. 10-106974).
【００１９】この発明は、硫黄酸化細菌の栄養源である
硫黄と菌体合成に必要な炭素源を同一組成物内にほぼ同
量共存させることで、効率良く脱窒を行わせることを可
能とした画期的な方法であり、しかも脱窒系内で生成さ
れるカルシウムイオンと硫酸イオンの量は表２の通りほ
ぼ等量でややカルシウムイオンが多く、常に中性（ｐＨ
７）付近を保てるため、ｐＨの低下による脱窒能の低下
は起こらない。The present invention makes it possible to efficiently perform denitrification by allowing sulfur, which is a nutrient of sulfur-oxidizing bacteria, and a carbon source necessary for bacterial cell coexistence in substantially the same amount in the same composition. As shown in Table 2, the amounts of calcium ions and sulfate ions generated in the denitrification system are almost equal, slightly large in calcium ions, and always neutral (pH
7) Since the vicinity can be maintained, a decrease in the denitrification ability due to a decrease in the pH does not occur.
【００２０】それに加えて、炭酸カルシウムは微粉を用
い、硫黄との等量混合溶融・急冷・破砕を行って得られ
る組成物であるので、その微小起伏の多い破断面全体に
硫黄酸化細菌が定着しやすい構造となっている。また、
粒の断面全体で一連の反応にあずかれるので非常に効率
が良く、組成物粒子を大きくすること、例えば５〜２５
ｍｍ程度とすることができるので、脱窒による窒素ガス
を粒子間にはらみ脱窒が停止してしまうことがなく、し
かも、粒子全体を窒素ガスが覆ってしまうこともない。In addition, since calcium carbonate is a composition obtained by mixing, melting, quenching, and crushing an equivalent amount of sulfur with fine powder, sulfur-oxidizing bacteria are established on the entire fractured surface with many fine undulations. It has a structure that is easy to do. Also,
Since the entire cross section of the grains is subjected to a series of reactions, the efficiency is very high, and the composition particles are enlarged, for example, 5 to 25.
Since the diameter can be set to about mm, nitrogen gas due to denitrification is not interposed between particles, so that denitrification does not stop, and nitrogen particles do not cover the whole particles.
【００２１】また、当該組成物は安全・容易に製造でき
るだけではなく、硫黄単体や石灰岩粒を各々混ぜて使用
することにより、水とのなじみが良い破断面を多く有す
ることからも脱窒に大きく寄与し、水中崩壊性も著しく
小さいので、長期に亘り効果が安定的に持続するという
利点もある。In addition, the composition can be manufactured safely and easily, and since it has a large number of fracture surfaces that are well compatible with water, it can be easily denitrified by using a mixture of simple sulfur and limestone particles. It also has the advantage that the effect is stably maintained over a long period of time because the water disintegration property is extremely small.
【００２２】[0022]
【発明が解決しようとする課題】本発明は、硫黄酸化細
菌の活動に必須である硫黄と菌体合成に必須である炭素
の補給を必要とせず、硝酸性窒素の脱窒を効率よく発現
させるためのｐＨ値７付近に反応系を維持・安定させ、
且つ、炭酸カルシウムと硫黄のみの組成物に比較して
１．５〜２．５倍の脱窒機能を発揮し、より高濃度の硝
酸性窒素をも脱窒・浄化することが可能な硝酸性窒素脱
窒基質を提供することを目的とする。DISCLOSURE OF THE INVENTION The present invention makes it possible to efficiently denitrify nitrate nitrogen without requiring supplementation of sulfur which is essential for the activity of sulfur-oxidizing bacteria and carbon which is essential for cell synthesis. To maintain and stabilize the reaction system around pH 7
In addition, it exhibits a denitrification function 1.5 to 2.5 times that of a composition containing only calcium carbonate and sulfur, and can denitrify and purify even higher concentrations of nitrate nitrogen. It is intended to provide a nitrogen denitrification substrate.
【００２３】[0023]
【課題を解決するための手段】本発明の請求項１に係る
硝酸性窒素脱窒基質においては、炭酸カルシウムを主成
分とする物質と硫黄とを主要組成に、微細孔隙を有する
物質を共存させた粒状物または塊状物として構成されて
いる。According to a first aspect of the present invention, there is provided a nitrate-nitrogen denitrification substrate, wherein a substance having calcium carbonate as a main component and sulfur have a main composition and a substance having fine pores coexist. It is configured as a granular or lump.
【００２４】本発明の請求項２に係る硝酸性窒素脱窒基
質においては、炭酸カルシウムを主成分とする物質を１
０〜１５重量部と硫黄１０重量部とを主要組成に、微細
孔隙を有する物質を１〜３重量部共存させた粒状物また
は塊状物として構成されている。[0024] In the nitrate nitrogen denitrifying substrate according to the second aspect of the present invention, the substance containing calcium carbonate as a main component is used in an amount of 1%.
It is constituted as a particulate or lump having a main composition of 0 to 15 parts by weight and 10 parts by weight of sulfur and 1 to 3 parts by weight of a substance having fine pores.
【００２５】本発明の請求項３に係る硝酸性窒素脱窒基
質においては、炭酸カルシウムを主成分とする物質と硫
黄とを主要組成に、微細孔隙を有する鉱産物および／ま
たはその加工物を共存させた粒状物または塊状物として
構成されている。In the nitrate nitrogen denitrifying substrate according to claim 3 of the present invention, a substance mainly composed of calcium carbonate and sulfur have a main composition, and a mineral product having fine pores and / or a processed product thereof coexist. It is configured as a granular or lump mass.
【００２６】本発明の請求項４に係る硝酸性窒素脱窒基
質においては、炭酸カルシウムを主成分とする物質を１
０〜１５重量部と硫黄１０重量部とを主要組成に、微細
孔隙を有する鉱産物および／またはその加工物を１〜３
重量部共存させた粒状物または塊状物として構成されて
いる。In the nitrate-nitrogen denitrification substrate according to claim 4 of the present invention, the substance containing calcium carbonate as a main component is not used.
0 to 15 parts by weight and 10 parts by weight of sulfur as main components, and mineral products having fine pores and / or processed products thereof of 1 to 3 parts by weight.
It is constituted as a granular material or a mass which coexists by weight.
【００２７】本発明の請求項５に係わる硝酸性窒素脱窒
基質においては	、炭酸カルシウムを主成分とする物
質と硫黄とを主要組成に、微細孔隙を有する炭化物を共
存させた粒状物または塊状物として構成されている。The nitrate nitrogen denitrification substrate according to the fifth aspect of the present invention is characterized in that a granular material having a main composition of a substance mainly composed of calcium carbonate and sulfur and a carbide having fine pores coexisted. It is configured as an object or lump.
【００２８】本発明の請求項６に係る硝酸性窒素脱窒基
質においては、炭酸カルシウムを主成分とする物質を１
０〜１５重量部と硫黄１０重量部とを主要組成に、微細
孔隙を有する炭化物を１〜３重量部共存させた粒状物ま
たは塊状物として構成されている。In the nitrate-nitrogen denitrification substrate according to claim 6 of the present invention, the substance containing calcium carbonate as a main component is not used.
It is constituted as a granulated or lump having a main composition of 0 to 15 parts by weight and 10 parts by weight of sulfur and 1 to 3 parts by weight of a carbide having fine pores.
【００２９】本発明の請求項７に係る硝酸性窒素脱窒基
質においては、炭酸カルシウムを主成分とする物質と硫
黄とを主要組成に、微細孔隙を有する鉱産物および／ま
たはその加工物と微細孔隙を有する炭化物を共存させた
粒状物または塊状物として構成されている。The nitrate-nitrogen denitrification substrate according to claim 7 of the present invention has a main composition of a substance mainly composed of calcium carbonate and sulfur, and has a fine pore and / or a processed product thereof. It is constituted as a granular material or a lump in which a carbide having pores coexists.
【００３０】本発明の請求項８に係る硝酸性窒素脱窒基
質においては、炭酸カルシウムを主成分とする物質を１
０〜１５重量部と硫黄１０重量部とを主要組成に、微細
孔隙を有する鉱産物および／またはその加工物と微細孔
隙を有する炭化物を１〜３重量部共存させた粒状物また
は塊状物として構成されている。[0030] In the nitrate nitrogen denitrifying substrate according to claim 8 of the present invention, the substance containing calcium carbonate as a main component is used as one substance.
Mainly composed of 0 to 15 parts by weight of sulfur and 10 parts by weight of sulfur, and as a granular material or lump in which a mineral product having fine pores and / or a processed product thereof and a carbide having fine pores coexist in 1 to 3 parts by weight. Have been.
【００３１】本発明の請求項９に係る硝酸性窒素脱窒基
質においては、炭酸カルシウム１０〜１５重量部と硫黄
１０重量部とを主成分に、珪藻土および／または籾殻燻
炭を１〜３重量部共存させた粒状物または塊状物として
構成されている。The nitrate nitrogen denitrification substrate according to claim 9 of the present invention comprises 10 to 15 parts by weight of calcium carbonate and 10 parts by weight of sulfur, and 1 to 3 parts by weight of diatomaceous earth and / or rice husk charcoal. It is constituted as a granular material or a lump which coexists partly.
【００３２】[0032]
【発明の実施の形態】この硝酸性窒素脱窒基質は、炭酸
カルシウムを主成分とする物質と硫黄とを主要組成に、
微細孔隙を有する物質を共存させた粒状物または塊状物
でなる。その組成物中で、炭酸カルシウムを主成分とす
る物質としては、炭酸カルシウム、石灰岩粉末および破
砕物、貝類の殻粉末および破砕物、貝化石粉末および破
砕物、ドロマイト粉末および破砕物、サンゴ粉末および
破砕物を用いることができる。BEST MODE FOR CARRYING OUT THE INVENTION The nitrate nitrogen denitrification substrate has a main composition of a substance mainly composed of calcium carbonate and sulfur,
It is a granular or lump coexisting with a substance having fine pores. In the composition, the substance containing calcium carbonate as a main component includes calcium carbonate, limestone powder and crushed material, shellfish powder and crushed material, shell fossil powder and crushed material, dolomite powder and crushed material, coral powder and Crushed material can be used.
【００３３】また、微細孔隙を有する物質のうち、鉱産
物および／またはその加工物としては珪藻土、珪藻土焼
成物、凝灰岩、坑火石、パーライト、真珠岩、有孔隙セ
ラミック、レンガ、ＡＬＣ、軽石、ポゾラン、シラス、
シラスバルーン、膨張頁岩焼成物、アタパルジャイト、
セピオライト、クリストバライト、セリサイト、酸性白
土、イライトを用いることができる。Of the substances having fine pores, mineral products and / or processed products thereof include diatomaceous earth, diatomite fired material, tuff, minestone, perlite, perlite, porous ceramics, brick, ALC, pumice, and pozzolan. , Shirasu,
Shirasu balloon, expanded shale fired material, attapulgite,
Sepiolite, cristobalite, sericite, acid clay, and illite can be used.
【００３４】その他、微細孔隙を有する炭化物としては
木炭、ヤシガラ炭、籾殻燻炭、石炭、竹炭、活性炭を用
いることができる。In addition, charcoal, coconut charcoal, rice husk charcoal, coal, bamboo charcoal, and activated carbon can be used as the carbide having fine pores.
【００３５】更に、その他の微細孔隙を有する物質とし
ては火山灰、土壌、フライアッシュ、サンゴ粉末および
破砕物、貝類の殻粉末および破砕物を用いることができ
る。Further, as other substances having fine pores, volcanic ash, soil, fly ash, coral powder and crushed material, shell powder of shellfish and crushed material can be used.
【００３６】なお、この粒状物または塊状物は炭酸カル
シウムを主成分とする物質と硫黄とを微細孔隙を有する
物質と混合した後に硫黄を１１２〜１２５℃程度の温度
で加熱溶融して急冷固化し、その固化物を破砕し或いは
造粒することにより得られる。その硫黄を加熱溶融する
ことに代えて、予め液状化された硫黄を用いることもで
きる。The granules or aggregates are obtained by mixing a substance mainly composed of calcium carbonate and sulfur with a substance having fine pores, and then heating and melting the sulfur at a temperature of about 112 to 125 ° C. to rapidly solidify the solid. Can be obtained by crushing or granulating the solidified product. Instead of heating and melting the sulfur, sulfur liquefied in advance can be used.
【００３７】本発明に用いる微細孔隙を有する物質の含
有水分は、概ね３０％以下であることが好ましく、ま
た、粒度は長径５mm以下が望ましく、さらに長径１mm以
下の粒度に調整することが最も望ましい。The water content of the substance having fine pores used in the present invention is preferably about 30% or less, and the particle size is desirably 5 mm or less in the major axis, and most desirably adjusted to the particle diameter of 1 mm or less in the major axis. .
【００３８】但し、籾殻燻炭や未固結のシラス、未固結
の火山灰、未固結の土壌等については特に粒度調整をせ
ずに使用することができる。However, rice husk charcoal, unconsolidated shirasu, unconsolidated volcanic ash, unconsolidated soil and the like can be used without particular adjustment of particle size.
【００３９】このようにして得られる硝酸性窒素脱窒基
質は硝酸性窒素に係る水質浄化に適し、高濃度の硝酸性
窒素の除去にも優れ、また、処理水ｐHが強酸性になる
こともない。The nitrate nitrogen denitrification substrate obtained in this way is suitable for purifying the water quality of nitrate nitrogen, is excellent in removing high-concentration nitrate nitrogen, and also makes the treated water pH strongly acidic. Absent.
【００４０】その有効性を確認するべく、本発明品とし
て炭酸カルシウム：１０重量部，硫黄：１０重量部に対
し、籾殻燻炭：３重量部を共存させた試料（本発明品
１）、籾殻燻炭：１重量部と珪藻土：１重量部とを共存
させた試料（本発明品２）、珪素土：２重量部を共存さ
せた試料（本発明品３）を作製した。また、比較例とし
て硫黄粒：１０重量部と炭酸カルシウム粒：１０重量部
とを混合した試料（比較例１）、硫黄：１０重量部と炭
酸カルシウム共存組成物：１０重量部とを混合した試料
（比較例２）を作製した。この試料の組成物としては粒
子径：５〜１０ｍｍ程度のものを用いた。In order to confirm its effectiveness, a sample (product 1 of the present invention) in which rice husk charcoal: 3 parts by weight coexisted with 10 parts by weight of calcium carbonate and 10 parts by weight of sulfur was used as the product of the present invention. A sample coexisting with 1 part by weight of sucrose and 1 part by weight of diatomaceous earth (Product 2 of the present invention) and a sample coexisting with 2 parts by weight of silicon earth (Product 3 of the present invention) were produced. As a comparative example, a sample in which 10 parts by weight of sulfur particles and 10 parts by weight of calcium carbonate particles were mixed (Comparative Example 1), and a sample in which 10 parts by weight of sulfur and 10 parts by weight of a composition coexisting with calcium carbonate were mixed. (Comparative Example 2) was produced. The composition of this sample used had a particle diameter of about 5 to 10 mm.
【００４１】その各試料により、硝酸性窒素：１５０ｍ
ｇ／ｌ、平均水温：２０℃の原水に、埼玉県熊谷市内の
暗渠水路より採収した河川底質を１ｗｔ％を添加した水
を対象とし、バッチ試験による脱窒処理した。その結果
は表１並びに図１のバッチ試験による硝酸性窒素の減少
推移・残存量ｍｇ／ｌで示す通りであり、本発明品はい
ずれも高濃度の硝酸性窒素の除去に優れることが確認で
きた。According to each sample, nitrate nitrogen: 150 m
g / l, average water temperature: 20 ° C., and 1% by weight of river sediment collected from a culvert canal in Kumagaya City, Saitama Prefecture, was subjected to a denitrification treatment by a batch test. The results are as shown in Table 1 and the change in the amount of nitrate nitrogen and the residual amount in mg / l by the batch test in FIG. 1, and it can be confirmed that all of the products of the present invention are excellent in removing high-concentration nitrate nitrogen. Was.
【００４２】[0042]
【表１】 [Table 1]
【００４３】また、各試料を用いた際の系内のｐＨの変
化を測定したところ、図２で示す通りであり、本発明品
では処理水ｐＨが強酸性になることがないことも確認で
きた。それと共に、各試料を用いて脱窒開始２０日後の
硫酸イオンとカルシウムイオンとの発生量ｍｇ／ｌを測
定したところ、表２で示す通りであった。Further, when the change in pH in the system when each sample was used was measured, it is as shown in FIG. 2, and it was confirmed that the pH of the treated water did not become strongly acidic in the product of the present invention. Was. At the same time, the amount of generated sulfate ion and calcium ion mg / l 20 days after the start of denitrification was measured using each sample, and the results were as shown in Table 2.
【００４４】[0044]
【表２】 [Table 2]
【００４５】それは、本発明品では図３で示すように炭
酸カルシウムと硫黄とが同一の粒内に共存しているだけ
でなく、硫黄酸化細菌の担体として有効と判断される微
細孔隙を有する物質も含み同一組成物としていることに
よる。また、栄養源としての硫黄、菌体合成に必要な炭
素を外部より供給する必要がなく、硫黄酸化細菌の活動
域がほぼ中性ｐＨで、微生物活性が高く維持される上、
さらに菌体定着・増殖のすみ場としての微細孔隙を同時
に与えることによる。このような組成により、測定され
るｐＨもほぼ中性でイオンバランスもよいことから脱窒
能が飛躍的に向上し、例えば停滞水中の１５０ｐｐｍを
超える高濃度の硝酸性窒素も確実に脱窒させることがで
き、水質環境の改善に大きく寄与できる。In the product of the present invention, as shown in FIG. 3, not only calcium carbonate and sulfur coexist in the same grain, but also a substance having fine pores judged to be effective as a carrier for sulfur-oxidizing bacteria. And the same composition. In addition, sulfur as a nutrient source, there is no need to externally supply carbon necessary for bacterial cell synthesis, the active area of the sulfur oxidizing bacteria is almost neutral pH, and the microbial activity is maintained at a high level.
Further, by providing micropores simultaneously as a place for colonization and growth of cells. With such a composition, the measured pH is almost neutral and the ion balance is good, so that the denitrification ability is remarkably improved. For example, the nitrate nitrogen having a high concentration exceeding 150 ppm in the stagnant water is surely denitrified. And can greatly contribute to the improvement of the water quality environment.
【００４６】これに対し、図４で示すような炭酸カルシ
ウムと硫黄を単独粒のまま混合する方法や炭酸カルシウ
ムと硫黄が共存する組成物では測定されるｐＨは中性で
あり、得られるイオンバランスも一見良好ではあるが、
硫黄酸化細菌の活動域は酸性になってしまい、微生物活
性が低下する。On the other hand, in the method of mixing calcium carbonate and sulfur alone as shown in FIG. 4 or in a composition in which calcium carbonate and sulfur coexist, the measured pH is neutral, and the resulting ion balance is low. Is also good at first glance,
The active area of the sulfur oxidizing bacteria becomes acidic, and the microbial activity decreases.
【００４７】[0047]
【発明の効果】以上述べた如く、本発明の請求項１に係
る硝酸性窒素脱窒基質に依れば、炭酸カルシウムを主成
分とする物質と硫黄とを主要組成に、微細孔隙を有する
物質を共存させた粒状物または塊状物でなるため、多肥
地帯の耕地暗渠排水等の高濃度の硝酸性窒素の除去にも
優れ、炭酸カルシウムと硫黄さらに微細孔隙を有する物
質とが同一の粒内に共存することにより、硫黄酸化細菌
の栄養源である硫黄は必要に応じ菌体により酸化され、
菌体合成に必要である炭素も共存しているため菌の増殖
がスムーズに行われると同時に、微細孔隙が菌体定着の
場となるので脱窒が効率良く行われる。さらに、ｐHバ
ランスが良好で、系内においてｐH値は６．５〜７．５
に保たれる。As described above, according to the nitrate-nitrogen denitrification substrate according to the first aspect of the present invention, a substance having a main composition of calcium carbonate as a main component and sulfur and a substance having fine pores It is also excellent in removing high-concentration nitrate nitrogen such as drainage from cultivated cultivated culverts in multi-fertilized areas, and calcium carbonate, sulfur, and substances having fine pores are in the same grain. By coexisting in, sulfur, which is a nutrient source of sulfur oxidizing bacteria, is oxidized by the cells as needed,
Since carbon necessary for cell synthesis is also present, the growth of the cells is carried out smoothly, and at the same time, the denitrification is carried out efficiently because the micropores serve as a place for cells to colonize. Furthermore, the pH balance is good, and the pH value is 6.5 to 7.5 in the system.
Is kept.
【００４８】本発明の請求項２に係る硝酸性窒素脱窒基
質に依れば、炭酸カルシウムを主成分とする物質を１０
〜１５重量部と硫黄１０重量部とを主要組成に、微細孔
隙を有する物質を１〜３重量部共存させた粒状物または
塊状物でなるため、多肥地帯の耕地暗渠排水等の高濃度
の硝酸性窒素の除去にも優れ、炭酸カルシウムを主成分
とする物質を１０〜１５重量部と硫黄１０重量部とを主
要組成に、微細孔隙を有する物質を１〜３重量部共存さ
せた粒状物または塊状物とが同一の粒内に共存すること
により、硫黄酸化細菌の栄養源である硫黄は必要に応じ
菌体により酸化され、菌体合成に必要である炭素も共存
しているため菌の増殖がスムーズに行われると同時に、
微細孔隙が菌体定着の場となるので脱窒が効率良く行わ
れる。さらに、ｐHバランスが良好で、系内においてｐH
値は６．５〜７．５に保たれる。According to the nitrate-nitrogen denitrification substrate according to the second aspect of the present invention, the substance containing calcium carbonate as a main component is not used.
１５15 parts by weight and 10 parts by weight of sulfur as the main composition, and a substance having fine pores in the form of granules or lumps coexisting in an amount of 1 to 3 parts by weight. Granular material which is excellent in removing nitrate nitrogen and has a main composition of 10 to 15 parts by weight of a substance mainly composed of calcium carbonate and 10 parts by weight of sulfur and 1 to 3 parts by weight of a substance having fine pores. Alternatively, the coexistence of agglomerates in the same grain causes sulfur, which is a nutrient source of sulfur-oxidizing bacteria, to be oxidized by the cells as needed, and the carbon required for cell synthesis is also present. At the same time as the proliferation is smooth,
Since the micropores provide a place for colonization of the cells, denitrification is performed efficiently. Furthermore, the pH balance is good, and the pH
The value is kept between 6.5 and 7.5.
【００４９】本発明の請求項３に係る硝酸性窒素脱窒基
質に依れば、炭酸カルシウムを主成分とする物質と硫黄
とを主要組成に、微細孔隙を有する鉱産物および／また
はその加工物を共存させた粒状物または塊状物でなるた
め、多肥地帯の耕地暗渠排水等の高濃度の硝酸性窒素の
除去にも優れ、炭酸カルシウムと硫黄さらに微細孔隙を
有する鉱産物および／またはその加工物とが同一の粒内
に共存することにより、硫黄酸化細菌の栄養源である硫
黄は必要に応じ菌体により酸化され、菌体合成に必要で
ある炭素も共存しているため菌の増殖がスムーズに行わ
れると同時に、微細孔隙が菌体定着の場となるので脱窒
が効率良く行われる。さらに、ｐHバランスが良好で、
系内においてｐH値は６．５〜７．５に保たれる。According to the nitrate-nitrogen denitrifying substrate according to claim 3 of the present invention, a mineral having a main composition of a substance mainly composed of calcium carbonate and sulfur, and having fine pores and / or a processed product thereof It is also excellent in removing high-concentration nitrate nitrogen, such as drainage from cultivated culverts in multi-fertilized areas, and is a mineral product having calcium carbonate and sulfur and fine pores and / or its processing because it is composed of granular or massive materials coexisting When the substance coexists in the same grain, sulfur, which is a nutrient source of the sulfur-oxidizing bacteria, is oxidized by the cells as needed, and the carbon necessary for cell synthesis is also present. At the same time, the denitrification is carried out efficiently because the micropores serve as a place for colonization of the bacterial cells. Furthermore, the pH balance is good,
The pH value is kept at 6.5 to 7.5 in the system.
【００５０】本発明の請求項４に係る硝酸性窒素脱窒基
質に依れば、炭酸カルシウムを主成分とする物質を１０
〜１５重量部と硫黄１０重量部とを主要組成に、微細孔
隙を有する鉱産物および／またはその加工物を１〜３重
量部共存させた粒状物または塊状物でなるため、多肥地
帯の耕地暗渠排水等の高濃度の硝酸性窒素の除去にも優
れ、炭酸カルシウムを主成分とする物質を１０〜１５重
量部と硫黄１０重量部とを主要組成に、微細孔隙を有す
る鉱産物および／またはその加工物を１〜３重量部共存
させた粒状物または塊状物とが同一の粒内に共存するこ
とにより、硫黄酸化細菌の栄養源である硫黄は必要に応
じ菌体により酸化され、菌体合成に必要である炭素も共
存しているため菌の増殖がスムーズに行われると同時
に、微細孔隙が菌体定着の場となるので脱窒が効率良く
行われる。さらに、ｐHバランスが良好で、系内におい
てｐH値は６．５〜７．５に保たれる。According to the nitrate-nitrogen denitrification substrate according to claim 4 of the present invention, the substance containing calcium carbonate as a main component is not used.
１５15 parts by weight and 10 parts by weight of sulfur, and 1 to 3 parts by weight of a mineral product having fine pores and / or a processed product thereof having a fine pore are present in the form of granules or aggregates. It is also excellent at removing high-concentration nitrate nitrogen such as culvert drainage, and has a main composition of 10 to 15 parts by weight of a substance mainly composed of calcium carbonate and 10 parts by weight of sulfur, and minerals having fine pores and / or By coexisting in the same grain a granular material or lump in which the processed product coexists 1 to 3 parts by weight, sulfur, which is a nutrient of sulfur oxidizing bacteria, is oxidized by the bacterial cells as necessary, Since the carbon necessary for the synthesis is also present, the growth of the bacteria is carried out smoothly, and at the same time, the denitrification is carried out efficiently because the micropores serve as a place for the cells to colonize. Furthermore, the pH balance is good, and the pH value is maintained at 6.5 to 7.5 in the system.
【００５１】本発明の請求項５に係る硝酸性窒素脱窒基
質に依れば、炭酸カルシウムを主成分とする物質と硫黄
とを主要組成に、微細孔隙を有する炭化物を共存させた
粒状物または塊状物でなるため、多肥地帯の耕地暗渠排
水等の高濃度の硝酸性窒素の除去にも優れ、炭酸カルシ
ウムと硫黄さらに微細孔隙を有する炭化物とが同一の粒
内に共存することにより、硫黄酸化細菌の栄養源である
硫黄は必要に応じ菌体により酸化され、菌体合成に必要
である炭素も共存しているため菌の増殖がスムーズに行
われると同時に、微細孔隙が菌体定着の場となるので脱
窒が効率良く行われる。さらに、ｐHバランスが良好
で、系内においてｐH値は６．５〜７．５に保たれる。According to the nitrate-nitrogen denitrification substrate according to claim 5 of the present invention, a granular material or a material in which a substance having calcium carbonate as a main component and sulfur having a main composition and a carbide having fine pores coexist. Because it is a lump, it is also excellent at removing high-concentration nitrate nitrogen such as drainage from cultivated culverts in multi-fertilized areas, and calcium carbonate, sulfur, and carbide having fine pores coexist in the same grain, resulting in sulfur. Sulfur, a nutrient source of the oxidizing bacteria, is oxidized by the cells as needed, and the carbon necessary for cell synthesis is also present, so that the bacteria can grow smoothly and at the same time, the micropores allow the cells to colonize. Denitrification is performed efficiently. Furthermore, the pH balance is good, and the pH value is maintained at 6.5 to 7.5 in the system.
【００５２】本発明の請求項６に係る硝酸性窒素脱窒基
質に依れば、炭酸カルシウムを主成分とする物質を１０
〜１５重量部と硫黄１０重量部とを主要組成に、微細孔
隙を有する炭化物を１〜３重量部共存させた粒状物また
は塊状物でなるため、多肥地帯の耕地暗渠排水等の高濃
度の硝酸性窒素の除去にも優れ、炭酸カルシウムを主成
分とする物質を１０〜１５重量部と硫黄１０重量部とを
主要組成に、微細孔隙を有する炭化物を１〜３重量部共
存させた粒状物または塊状物とが同一の粒内に共存する
ことにより、硫黄酸化細菌の栄養源である硫黄は必要に
応じ菌体により酸化され、菌体合成に必要である炭素も
共存しているため菌の増殖がスムーズに行われると同時
に、微細孔隙が菌体定着の場となるので脱窒が効率良く
行われる。さらに、ｐHバランスが良好で、系内におい
てｐH値は６．５〜７．５に保たれる。According to the nitrate-nitrogen denitrification substrate according to claim 6 of the present invention, a substance containing calcium carbonate as a main component is used.
１５15 parts by weight and 10 parts by weight of sulfur in the main composition, it is a granular or lump coexistence of 1-3 parts by weight of carbide having fine pores, so high concentration of cultivated culvert drainage etc. Granular material which is excellent in removing nitrate nitrogen and has a main composition of 10 to 15 parts by weight of a substance mainly composed of calcium carbonate and 10 parts by weight of sulfur and 1 to 3 parts by weight of a carbide having fine pores. Alternatively, the coexistence of agglomerates in the same grain causes sulfur, which is a nutrient source of sulfur-oxidizing bacteria, to be oxidized by the cells as needed, and the carbon required for cell synthesis is also present. Proliferation is carried out smoothly, and at the same time, the micropores serve as a place for cells to colonize, so that denitrification is carried out efficiently. Furthermore, the pH balance is good, and the pH value is maintained at 6.5 to 7.5 in the system.
【００５３】本発明の請求項７に係る硝酸性窒素脱窒基
質に依れば、炭酸カルシウムを主成分とする物質と硫黄
とを主要組成に、微細孔隙を有する鉱産物および／また
はその加工物と微細孔隙を有する炭化物を共存させた粒
状物または塊状物でなるため、多肥地帯の耕地暗渠排水
等の高濃度の硝酸性窒素の除去にも優れ、炭酸カルシウ
ムと硫黄さらに、微細孔隙を有する鉱産物および／また
はその加工物と微細孔隙を有する炭化物とが同一の粒内
に共存することにより、硫黄酸化細菌の栄養源である硫
黄は必要に応じ菌体により酸化され、菌体合成に必要で
ある炭素も共存しているため菌の増殖がスムーズに行わ
れると同時に、微細孔隙が菌体定着の場となるので脱窒
が効率良く行われる。さらに、ｐHバランスが良好で、
系内においてｐH値は６．５〜７．５に保たれる。According to the nitrate-nitrogen denitrification substrate according to claim 7 of the present invention, a mineral mainly having calcium carbonate as a main component and sulfur and having fine pores and / or a processed product thereof It is also excellent in removing high-concentration nitrate nitrogen such as drainage from cultivated cultivated culverts in multifertilized areas, and has calcium carbonate and sulfur, as well as fine pores, because it is made of granules or aggregates coexisting with carbides having fine pores The coexistence of mineral products and / or their processed products and carbides having micropores in the same grain allows sulfur, which is a nutrient source of sulfur-oxidizing bacteria, to be oxidized by the bacterial cells as necessary and required for bacterial cell synthesis. In addition, the presence of carbon, which is also present, allows bacteria to grow smoothly, and at the same time, denitrification is performed efficiently because the micropores serve as a place for cells to colonize. Furthermore, the pH balance is good,
The pH value is kept between 6.5 and 7.5 in the system.
【００５４】本発明の請求項８に係る硝酸性窒素脱窒基
質に依れば、炭酸カルシウムを主成分とする物質を１０
〜１５重量部と硫黄１０重量部とを主要組成に、微細孔
隙を有する鉱産物および／またはその加工物と微細孔隙
を有する炭化物を１〜３重量部共存させた粒状物または
塊状物でなるため、多肥地帯の耕地暗渠排水等の高濃度
の硝酸性窒素の除去にも優れ、炭酸カルシウムを主成分
とする物質を１０〜１５重量部と硫黄１０重量部とを主
要組成に、微細孔隙を有する鉱産物および／またはその
加工物と微細孔隙を有する炭化物を１〜３重量部共存さ
せた粒状物または塊状物とが同一の粒内に共存すること
により、硫黄酸化細菌の栄養源である硫黄は必要に応じ
菌体により酸化され、菌体合成に必要である炭素も共存
しているため菌の増殖がスムーズに行われると同時に、
微細孔隙が菌体定着の場となるので脱窒が効率良く行わ
れる。さらに、ｐHバランスが良好で、系内においてｐH
値は６．５〜７．５に保たれる。According to the nitrate-nitrogen denitrification substrate according to claim 8 of the present invention, a substance containing calcium carbonate as a main component is used.
To 15 parts by weight and 10 parts by weight of sulfur as a main component, and a particulate or lump in which a mineral product having fine pores and / or a processed product thereof and a carbide having fine pores are present in an amount of 1 to 3 parts by weight. It is also excellent at removing high concentration nitrate nitrogen such as culvert drainage in cultivated cultivated cultivation in the fertilizer zone. The main composition is 10-15 parts by weight of a substance mainly composed of calcium carbonate and 10 parts by weight of sulfur. The presence of minerals and / or processed products thereof and granules or aggregates in which 1 to 3 parts by weight of carbides having micropores coexist in the same grain, thereby providing sulfur, a nutrient source of sulfur-oxidizing bacteria. Is oxidized by the cells as necessary, and the carbon necessary for cell synthesis is also present, so that the growth of the cells is performed smoothly,
Since the micropores provide a place for colonization of the cells, denitrification is performed efficiently. Furthermore, the pH balance is good, and the pH
The value is kept between 6.5 and 7.5.
【００５５】本発明の請求項９に係る硝酸性窒素脱窒基
質に依れば、炭酸カルシウム１０〜１５重量部と硫黄１
０重量部とを主成分に、珪藻土および／または籾殻燻炭
を１〜３重量部共存させた粒状物または塊状物でなるた
め、多肥地帯の耕地暗渠排水等の高濃度の硝酸性窒素の
除去にも優れ、炭酸カルシウム１０〜１５重量部と硫黄
１０重量部とを主成分に、珪藻土および／または籾殻燻
炭を１〜３重量部共存させた粒状物または塊状物とが同
一の粒内に共存することにより、硫黄酸化細菌の栄養源
である硫黄は必要に応じ菌体により酸化され、菌体合成
に必要である炭素も共存しているため菌の増殖がスムー
ズに行われると同時に、微細孔隙が菌体定着の場となる
ので脱窒が効率良く行われる。さらに、ｐHバランスが
良好で、系内においてｐH値は６．５〜７．５に保たれ
る。According to the nitrate-nitrogen denitrification substrate according to claim 9 of the present invention, 10 to 15 parts by weight of calcium carbonate and sulfur 1
0 parts by weight, and 1 to 3 parts by weight of diatomaceous earth and / or rice husk charcoal coexist in a granular or lump material. It is also excellent in removal. Granules or lumps containing 10 to 15 parts by weight of calcium carbonate and 10 parts by weight of sulfur as main components and 1 to 3 parts by weight of diatomaceous earth and / or rice husk charcoal coexist in the same grain. By coexisting, sulfur, which is a nutrient source of sulfur-oxidizing bacteria, is oxidized by the cells as needed, and the carbon required for cell synthesis also coexists, so that the growth of the cells is performed smoothly, Since the micropores provide a place for colonization of the cells, denitrification is performed efficiently. Furthermore, the pH balance is good, and the pH value is maintained at 6.5 to 7.5 in the system.
【図１】本発明に係る硝酸性窒素脱窒基質による硝酸性
窒素の残存量，即ち、硝酸性窒素の減少推移を比較例
１，２と共に示すグラフである。FIG. 1 is a graph showing the remaining amount of nitrate nitrogen by a nitrate nitrogen denitrification substrate according to the present invention, that is, a decrease transition of nitrate nitrogen, together with Comparative Examples 1 and 2.
【図２】本発明に係わる硝酸性窒素脱窒基質を用いた際
の系内ｐHの変化を比較例１，２と共に示すグラフであ
る。FIG. 2 is a graph showing a change in pH in the system when a nitrate nitrogen denitrification substrate according to the present invention is used, together with Comparative Examples 1 and 2.
【図３】本発明に係る硝酸性窒素脱窒基質の内部構造を
模式的に示す説明図である。FIG. 3 is an explanatory view schematically showing an internal structure of a nitrate nitrogen denitrification substrate according to the present invention.
【図４】硫黄粒子と炭酸カルシウム粒子とを単に混合し
たものの内部構造を模式的に示す説明図である。FIG. 4 is an explanatory view schematically showing the internal structure of a simple mixture of sulfur particles and calcium carbonate particles.
─────────────────────────────────────────────────────
────────────────────────────────────────────────── ───
【手続補正書】[Procedure amendment]
【提出日】平成１０年１０月１４日（１９９８．１０．
１４）[Submission date] October 14, 1998 (1998.10.
14)
【手続補正１】[Procedure amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】０００２[Correction target item name] 0002
【補正方法】変更[Correction method] Change
【補正内容】[Correction contents]
【０００２】[0002]
【従来の技術】水質を浄化するための硝酸性窒素除去技
術のうち、例えば、メタノールや汚泥中の有機炭素源を
水素供与体として従属栄養性脱窒を行わせる方法は従来
から知られている。この方法は目的微生物以外の分解系
の影響を受け、基質当たりの脱窒効率は低いが、比較的
簡単に硝酸性窒素を脱窒させることができるので、脱窒
処理に用いたメタノールや汚泥を外界に排出しないよう
厳しく管理された処理設備において実施される。即ち、
単一の脱窒槽に被処理水を通水するだけでは脱窒操作を
完了させることができず、多くの処理過程や処理槽・設
備が必要となる。2. Description of the Related Art Among nitrate nitrogen removal techniques for purifying water quality, for example, a method of performing heterotrophic denitrification using methanol or an organic carbon source in sludge as a hydrogen donor has been known. . This method is affected by decomposition systems other than the target microorganism, and has a low denitrification efficiency per substrate.However, since nitrate nitrogen can be denitrified relatively easily, the methanol and sludge used in the denitrification treatment can be removed. It is carried out in processing equipment that is strictly controlled so as not to be released to the outside world. That is,
Simply passing the water to be treated through a single denitrification tank cannot complete the denitrification operation, and requires many treatment steps and treatment tanks and equipment.
【手続補正２】[Procedure amendment 2]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００２１[Correction target item name] 0021
【補正方法】変更[Correction method] Change
【補正内容】[Correction contents]
【００２１】また、当該組成物は安全・容易に製造でき
るだけではなく、硫黄単体や石灰岩粒を各々混ぜて使用
するより、水とのなじみが良い破断面を多く有すること
からも脱窒に大きく寄与し、水中崩壊性も著しく小さい
ので、長期に亘り効果が安定的に持続するという利点も
ある。In addition, the composition can not only be manufactured safely and easily, but also greatly contributes to denitrification because it has a large number of fracture surfaces that are well compatible with water, compared with the use of a mixture of simple sulfur and limestone particles. In addition, since the water disintegration property is extremely small, there is an advantage that the effect is stably maintained for a long time.
【手続補正３】[Procedure amendment 3]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００２７[Correction target item name] 0027
【補正方法】変更[Correction method] Change
【補正内容】[Correction contents]
【００２７】本発明の請求項５に係わる硝酸性窒素脱窒
基質においては、炭酸カルシウムを主成分とする物質と
硫黄とを主要組成に、微細孔隙を有する炭化物を共存さ
せた粒状物または塊状物として構成されている。The nitrate nitrogen denitrifying substrate according to claim 5 of the present invention is characterized in that a granular substance or a massive substance in which a substance having calcium carbonate as a main component and sulfur have a main composition and a carbide having fine pores coexist. Is configured as
【手続補正４】[Procedure amendment 4]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００４６[Correction target item name] 0046
【補正方法】変更[Correction method] Change
【補正内容】[Correction contents]
【００４６】これに対し、図４で示すような炭酸カルシ
ウムと硫黄を単独粒のまま混合する方法では測定される
ｐＨは中性であり、得られるイオンバランスも一見良好
ではあるが、硫黄酸化細菌の活動域は酸性になってしま
い、微生物活性が低下する。On the other hand, in the method of mixing calcium carbonate and sulfur alone as shown in FIG. 4, the measured pH is neutral, and the obtained ion balance is apparently good, but the sulfur-oxidizing bacteria The active area becomes acidic and the microbial activity decreases.
Claims (9)
黄とを主要組成に、微細孔隙を有する物質を共存させた
粒状物または塊状物でなることを特徴とする硝酸性窒素
脱窒基質。1. A nitrate-nitrogen denitrification substrate characterized in that it is a granular or massive substance having a main composition of a substance mainly composed of calcium carbonate and sulfur and a substance having fine pores coexisting therewith.
０〜１５重量部と硫黄１０重量部とを主要組成に、微細
孔隙を有する物質を１〜３重量部共存させた粒状物また
は塊状物でなることを特徴とする請求項１に記載の硝酸
性窒素脱窒基質。2. A substance containing calcium carbonate as a main component.
The nitric acid according to claim 1, wherein the main component is 0 to 15 parts by weight and 10 parts by weight of sulfur, and 1 to 3 parts by weight of a substance having fine pores coexists. Nitrogen denitrification substrate.
黄とを主要組成に、微細孔隙を有する鉱産物および／ま
たはその加工物を共存させた粒状物または塊状物でなる
ことを特徴とする請求項１に記載の硝酸性窒素脱窒基
質。3. A particulate or massive material having a main composition of calcium carbonate as a main component and sulfur and a coexisting mineral product having fine pores and / or a processed product thereof. Item 4. The nitrate nitrogen denitrification substrate according to Item 1.
０〜１５重量部と硫黄１０重量部とを主要組成に、微細
孔隙を有する鉱産物および／またはその加工物を１〜３
重量部共存させた粒状物または塊状物でなることを特徴
とする請求項３に記載の硝酸性窒素脱窒基質。4. The method according to claim 1, wherein the main component is calcium carbonate.
0 to 15 parts by weight and 10 parts by weight of sulfur as main components, and mineral products having fine pores and / or processed products thereof of 1 to 3 parts by weight.
4. The nitrate-nitrogen denitrification substrate according to claim 3, wherein the substrate is composed of a granular material or a massive material coexisting in parts by weight.
黄とを主要組成に、微細孔隙を有する炭化物を共存させ
た粒状物または塊状物でなることを特徴とする請求項１
に記載の硝酸性窒素脱窒基質。5. A granular material or a massive material having a main composition of a substance mainly composed of calcium carbonate and sulfur and a coexisting carbide having fine pores.
The nitrate nitrogen denitrification substrate according to the above.
０〜１５重量部と硫黄１０重量部とを主要組成に、微細
孔隙を有する炭化物を１〜３重量部共存させた粒状物ま
たは塊状物でなることを特徴とする請求項５に記載の硝
酸性窒素脱窒基質。6. A substance containing calcium carbonate as a main component.
The nitric acid according to claim 5, characterized in that it is a granular material or an agglomerate in which 0 to 15 parts by weight and 10 parts by weight of sulfur have a main composition and 1 to 3 parts by weight of a carbide having fine pores coexist. Nitrogen denitrification substrate.
黄とを主要組成に、微細孔隙を有する鉱産物および／ま
たはその加工物と微細孔隙を有する炭化物を共存させた
粒状物または塊状物でなることを特徴とする請求項１に
記載の硝酸性窒素脱窒基質。7. A granular or massive material having a main composition of a substance mainly composed of calcium carbonate and sulfur and a coexisting mineral product having fine pores and / or a processed product thereof and a carbide having fine pores. The nitrate nitrogen denitrification substrate according to claim 1, wherein
０〜１５重量部と硫黄１０重量部とを主要組成に、微細
孔隙を有する鉱産物および／またはその加工物と微細孔
隙を有する炭化物を１〜３重量部共存させた粒状物また
は塊状物でなることを特徴とする請求項７に記載の硝酸
性窒素脱窒基質。8. A substance containing calcium carbonate as a main component.
It is a granular or lump having a main composition of 0 to 15 parts by weight of sulfur and 10 parts by weight of sulfur and 1 to 3 parts by weight of a mineral product having fine pores and / or a processed product thereof and a carbide having fine pores of 1 to 3 parts by weight. The nitrate nitrogen denitrification substrate according to claim 7, characterized in that:
１０重量部とを主成分に、珪藻土および／または籾殻燻
炭を１〜３重量部共存させた粒状物または塊状物でなる
ことを特徴とする請求項１に記載の硝酸性窒素脱窒基
質。9. A granular or lump material comprising 10 to 15 parts by weight of calcium carbonate and 10 parts by weight of sulfur and 1 to 3 parts by weight of diatomaceous earth and / or rice husk charcoal. The nitrate nitrogen denitrification substrate according to claim 1.
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27192098A JP4032199B2 (en) | 1998-09-25 | 1998-09-25 | Nitrate nitrogen denitrification substrate |
| US09/787,793 US7109022B1 (en) | 1998-09-25 | 1999-09-24 | Composition containing calcium carbonate particles dispersed in sulfur for removing nitrate nitrogen |
| PCT/JP1999/005226 WO2000018694A1 (en) | 1998-09-25 | 1999-09-24 | Denitrifying composition for removing nitrate nitrogen and process for producing the same |
| EP99944817A EP1129996A4 (en) | 1998-09-25 | 1999-09-24 | Denitrifying composition for removing nitrate nitrogen and process for producing the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27192098A JP4032199B2 (en) | 1998-09-25 | 1998-09-25 | Nitrate nitrogen denitrification substrate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2000093997A true JP2000093997A (en) | 2000-04-04 |
| JP4032199B2 JP4032199B2 (en) | 2008-01-16 |
Family
ID=17506718
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP27192098A Expired - Lifetime JP4032199B2 (en) | 1998-09-25 | 1998-09-25 | Nitrate nitrogen denitrification substrate |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4032199B2 (en) |
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